Malicious Office (OLE) / .XLSX — malware analysis report

Static analysis result for SHA-256 f8bfb70a905ebcc0…

MALICIOUS

Office (OLE) / .XLSX

329.0 KB Created: 2006-09-16 00:00:00 Authoring application: Microsoft Excel
MD5: 9dfa6996cbc1f126c7aee33e9794a57f SHA-1: f42b5a18d04d366fc31a70d40831a7ad35aff558 SHA-256: f8bfb70a905ebcc0a1611f005aa7149873f86e91f849818b3f1976cb4a0216dd
160 Risk Score

Malware Insights

MITRE ATT&CK
T1059.005 Visual Basic for Applications T1204.002 Malicious File T1059.001 PowerShell T1059.003 Windows Command Shell

The sample contains Excel 4.0 macros, indicated by the OLE_XLM_AUTOOPEN and OLE_XLM_DANGEROUS_FN heuristics. The SC_STR_SHELLEXEC firing suggests the macros are attempting to execute external commands. The embedded URL likely points to a second-stage payload. The ClamAV detection further confirms its malicious nature as a downloader.

Heuristics 5

  • ClamAV: Doc.Downloader.Docusign0521-9864805-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Doc.Downloader.Docusign0521-9864805-0
  • Reference to ShellExecute API high SC_STR_SHELLEXEC
    Reference to ShellExecute API
  • XLM Auto_Open with dangerous formula APIs high OLE_XLM_DANGEROUS_FN
    Excel 4.0 macro sheet contains an Auto_Open / Auto_Close entry and dangerous XLM formula APIs that can invoke programs, write files, or transfer control without VBA.
  • Excel 4.0 (XLM) macro sheet present medium OLE_XLM_AUTOOPEN
    Workbook contains an Excel 4.0 macro sheet sub-stream — XLM is rarely seen in modern legitimate workbooks and was a major Office malware vector during 2020-2022.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://bemojo.com/ds/161120.gif�

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
xlm_macros.txt
c7e4e7ed3c1ce4a0357cad7ea2d4765567912ff9637c55ef23ac64833b3a62a6
xlm-macro oletools.olevba.extract_all_macros (XLM macro listing) 6274 bytes